She was accused of murdering Miss Low but a jury convicted her of the lesser charge of culpable homicide.

A trial at the High Court in Aberdeen heard from Miss Low’s then-pregnant daughter, Jamie-Lee Low, who broke down in tears as she told of the moment Russell stabbed her mother to death in front of her.

She said: “Siobhan came out and she had a knife in her hand – she was shouting and screaming.

“I tried to get in the middle and told Siobhan to stop because I was pregnant.

“They were fighting and I was screaming for help. I watched her stab my mum – I watched her stab the knife in to my mum’s chest or belly area.

“After she stabbed my mum, her and Siobhan ended up on the floor – my mum was lying on the floor and Siobhan held the knife to my mum’s throat.”

Jamie-Lee’s older sister, Demi Hodge, 20, then appeared on the scene and grabbed Russell’s hand that was holding the knife before Russell fled to her flat.

The jury was told police had been called to Miss Low’s home the previous day following reports of a disturbance between Russell and Miss Low – with one witness telling the court they had brawled over a £10 debt.

The court later heard Miss Low suffered a single stab wound to the heart and was rushed to Dundee’s Ninewells Hospital.

She suffered a cardiac arrest before undergoing surgery in a bid to repair the damage to her left ventricle.

Following the operation she suffered a further four cardiac arrests before being pronounced dead at 5.19pm.

A knife was later found under the kitchen sink in Russell’s home that had her DNA on the handle and Miss Low’s on the blade.